Dowel bar or tie bar supporting side forms



4, 1956 N. HELTZEL 2,772,463

DOWEL. BAR 0R TIE BAR SUPPORTING SIDE FORMS Filed June 16, 1951 2Sheets-Sheet l INVENTOR JOHN N. HELTZEL.

ATTORNEYS 6.. 4, 1956 HELTZEL 237mm DOWEL BAR OR TIE BAR SUPPORTING SIDEFORMS Filed June 16. 195] 2 Sheets-Sheet 2 i #3,, FIG. 3.

INVENTOR ATTORNEYS United States Patent DOWEL BAR OR TIE BAR SUPPORTINGSIDE FORMS John N. Heltzel, Warren, Ohio; The Union Savings & TrustCompany, Warren, Ohio, and Carl J. Heltzel, executors of said John N.Heltzel, deceased Application June 16, 1951, Serial No. 231,981

Claims. (Cl. 25-118) The present invention relates to improvements indowel bar or tie bar supporting side forms and is a continuationin-partof my co-pending application, Serial No. 697,699, filed September 18,1946, now Patent No. 2,636,426, and entitled Dowel Bar Adjusting andAligning Devices.

An object of the present invention is to provide an improved device ofthis chaarcter for use in connection with dowel or tie bars for loadtransfer devices currently employed in connection with concreteconstructions, such as airport runways, concrete roads and the like, inwhich individual slabs of concrete are individually poured and laid withdeformed tie bars tying adjacent slabs together in a unitaryconstruction which nevertheless admits of local expansion andcontraction of the individual slabs when plain bars are installed.

In one aspect the invention is concerned with the supporting of dowelbars in a bulkhead or side form which carries a grooving strip forforming a groove in the edge of the concrete slab. A critical phase ofthis development is the passing of the tie bars through the form and thegrooving strip. In view of the fact that the tie bars are provided withlugs or protuberances (these tie bars or reinforcing bars are termeddeformed bars because of the protuberances or roughness on the outsidesurface), such outside rough surface interfers with the stripping of theforms from the dowel bars. Moreover such protuberances or roughness ofthe tie bars as a practical matter preclude the possibility of readilyremoving or stripping the side forms over the bars without injury to theconcrete slab; and it is another object of the invention to overcomethis difliculty.

Another object of the present invention is to provide an improved deviceof this kind in which lighter gauge material for the forms may beutilized at the same time increasing the strength of the form over thatof the conventional type so that the form will be able to withstandheavier machinery rolling on the top tread thereof, such as is usedparticularly in the construction of airports where extremely thickslabs, that is, of two or three feet or greater thickness, areconstructed.

A further object of the present invention is to provide an improved sideform into which means are incorporated for supporting the dowel bars atthe proper elevation and for serving as guides between the form and thedowel bars during the stripping operation, whereby disturbance of thebars and the slab is prevented.

A still further object of the present invention is to provide animproved structure in which the guides will secure the grooving strip tothe side form and also prevent the soft concrete from passing throughthe dowel bar openings and filling up the inside of the grooving strip.

With the foregoing and other objects in view, the invention will behereinafter more fully described and more particularly pointed out inthe appended claims.

In the drawings, in which the same parts are denoted 2,772,468 FatentedDec. 4, 1956 Figure 1 is a fragmentary isometric projection of anaccordance with the present invention and shown as applied to an airportrunway or the like.

Figure 2 is a fragmentary isometric projection of the airport runwayafter the side form has been stripped from the dowel bars,

Figure 3 is a sectional view taken on the line 3-3 of Figure l,

Figure 4 is a sectional view taken on the line 4-4 of Figure 1,

Figure 5 is a perspective view of the improved side form taken lookingat the inner side thereof.

Figure 6 is a sectional view taken on the line 6-6 of Figure 5,

Figure 7 is an isometric projection of one of the deformed dowel bars,

Figure 8 is a sectional view taken on the line 8-8 of Figure 7,

Figure 9 is a sectional view taken on the line 9-9 of Figure 7,

Figure 10 is a sectional view taken on the line 10-10 of Figure 3, and

Figure 11 is a fragmentary sectional view illustrating the honey-combingor voiding of the bar when the bar is placed in position first and theconcrete then poured.

Referring more particularly to the drawings, 10 indicates the verticalweb of the improved side form, 11 the base, 12 the top rail and 13 theupstanding base flange. A substantially vertical flange 14 extendsdownwardly a short distance from the free edge of the top rail 12 inspaced apart substantially parallel relation to the upper portion of thevertical web 10. A substantially horizontal flange 15 extends inwardlyfrom the upper free edge of the base flange 13 for a short distancetowards the ver tical web 10.

An edge grooving strip comprises a vertical wall 16, a flange 17extending upwardly and inwardly from the upper edge of the wall 16toward the vertical web 10 of the side form and a flange 18 extendingdownwardly and inwardly from the lower edge of the flange 17 toward thevertical web 10 of the side form. The grooving strip may be secured bytubular members 19 to the vertical web 10 of the side form with the freeedges of the flanges 17 and 18 engaging the outer face of the web 10.

Each tubular member 19 extends through horizontally aligned openings 20and 21 formed in the vertical web 10 by the same reference numeralsthroughout the several 7 views,

and the vertical wall 16 and the opposite end portions of the members 19extend beyond the outer face of the wall 16 and the inner face of theweb 1'0. The opposite extended end portions of each member 19 are rolledover i to provide flaring lips 22 and 23 which tightly engage the innerface of the web 10 and the outer face of the wall 16 around the openings20 and 21.

Diagonal supports or stake pockets 24 which may be in the form of barsare secured to the side form at horizontally spaced apart locations.Each support 24 extends at an angle of the order of forty-five degreesto the web 10 and the base 11 and the lower front and rear edges of eachsupport may engage the upper face of j the base 11 and the inner face ofthe base flange 13 as indicated at 25 and 26 in Figures 3 and 4,although the front edge in Figure 1 is shown spaced from the flange 13.The upper front and rear edges of each support 24 engage the inner faceof the web 10 and the under face of the top rail 12 as indicated at 27and 28.

3 cured to the vertical flange 14 and the horizontal flange 15 of theside form by welding 30 or the like.

A longitudinally extending brace 31 which may be of angle iron formationin cross section has the free edges of its horizontal flange 32 andvertical flange 33 secured to the outer faces of the supports 24 and 29as by welding 34 or the like. Each of the supports 24 has an aperture 35therethrough which is in alignment with an aperture 36 in the base 11. Astake 37 extends through each pair of aligned apertures 35 and 36 andmaybe driven into the subgrade 38 for anchoring the side form in position.Each of the supports 24 also has a substantially horizontally extendingthrough passageway 39 which is in alignment with the bore of the tubularmember 19 and the vertical flange 33 of the brace 31 has throughopenings 40 one of which is in registry with each of the passageways 39of the supports 24.

The passageways 39 are downwardly and laterally offset with respect tothe apertures 35 of the supports 24 so that the stakes 37 will notinterfere with the passage of dowel bars 41 through the openings 40, thepassageways 39 and the tubular members 19.

, Each support 29 has a substantially horizontally extendingthrough-passageway 42 and the vertical flange 33 of the brace 31 hasopenings 43 one of which is in alignment with each of the passageways42. The vertical web of the side form and the vertical wall 16 of thegrooving strip have openings 44 and 45 which are in registry with thepassageways 42. A sleeve 46 extends through each passageway 42 and isreceived by the aligned openings 43, 44 and 45. The opposite outer endsof the sleeves 46 are substantially flush with the outer faces of thewall 16 and the flange 33 so as to cover the sharp edges of the openings43 and 45. Each sleeve 46 may be restricted against longitudinalmovement by being secured to the vertical web 10, the wall 16 and theflange 33 by welding 47 or the like.

Additional stakes, one of which is shown at 37a in Figures 1 and 3 ofthe drawings, may be positioned in the spaces between certain ofadjacent diagonal braces 24 and 29. .and extend through suitablevertically aligned openings 50 formed in the base 11 and the horizontalflange 32 of the brace 31. Smooth or plain bars 41a may be positioned inother spaces between adjacent diagonal braces 24 and 29 and are receivedby horizontally aligned openings 51 in the vertical flange 33 of thebrace 31, the vertical web 10 and the vertical wall 16 of the groovingstrip.

As illustrated in Figure 6 of the drawings, a tubular member 19 isreceived by the openings 51 of the wall 10 and the wall 16 to assist insecuring the grooving strip to the vertical web 10 of the form. The bars41a will be freely received by these members 19.

It will be noted that these bars 41a do not pass through the diagonalbraces 24 and 29. This is important because these bars are some timesspaced very close so this would preclude the possibility of having somany diagonal braces. The longitudinal brace 31 is utilized as abar-aligning-member support which precludes the necessity of the barspassing through the passageways 39 and 42 in the braces 24 and 29. Thelongitudinal brace 31 will accommodate the insertion of the additionalstakes 37a.

In the use of the device the side form is positioned in the conventionalmanner with the base 11 thereof resting upon the upper surface of thesubgrade 38. The stakes 37 will be inserted into the apertures 35 of thesupports 24 and the apertures 36 of the base 11 and driven into thesubgrade 38 to anchor the side form in proper position. The additionalstakes 3701 may then be inserted into the openings 50 in the flange 32of the brace 31 and the base 11 of the form and driven into the subgradeto provide additional anchoring means.

The dowel bars 41 will then be'inserte'dinto the openings 40 of thebrace 31, the passageways 39 of the supports 24 and the tubular members19 so that substantially half of the length of each bar 41 will extendoutwardly of the vertical web 10 of the side form. Other bars 41 will beinserted through the sleeves 46 so that substantially half of the lengthof each bar extends outwardly beyond the vertical web 10. The smoothbars 41a will be inserted into the openings 51 in the flange 33 of thebrace 31, the web 10 of the form and the wall 16 of the grooving stripso that substantially half of the length of each bar 41a will extendoutwardly of the vertical web of the side form. The bars 41 and 41a willnow be supported in their proper elevated positions.

The concrete for forming a slab 48 will then be poured in theconventional manner and permitted to harden or semi-harden. The sideform will then be removed or stripped from the bars 41 and 41a by firstwithdrawing the stakes 37 and 37a and then laterally removing the sideform from the slab 48. It Will be noted particularly from Figures 6, 7and 8 of the drawings that the bars 41 have on their outer surfacesprotuberances or lugs 49 which are arcuate. The lugs 49 are shown asarranged in two longitudinal rows which are angularly offset from oneanother and the lugs of each row are longitudinally staggered withrespect to one another.

The edges of the openings 20 and 44 of the vertical web 10 and theopenings 21 and 45 of the vertical wall 16 are raw or sharp. These sharpedges would preclude the possibility of the side form and the groovingstrip being moved laterally during the stripping operation withoutdamage to the concrete slab or to the form structures. The provision ofthe tubular members 19 and the sleeves 46 cover the sharp edges of theopenings so that the bars 41 and especially the lugs 49 thereof areprevented from contacting these sharp edges. The side form and thegrooving strip are therefore easily stripped from the bars 41 withoutdamage to the bars, the concrete or the forms.

When the side form has been stripped from the bars 41 and 41asubstantially half of each bar will extend outwardly from the concreteslab 48, as can be seen particularly in Figure 2 of the drawings, andthe side form may be set up so that a second concrete slab may be pouredaround the exposed portions of the bars 41 and 41a.

The tubular members 19 and the sleeves 46 will not only function topermit easy stripping of the form from the bars 41, but will alsosupport the bars in proper elevated position and will serve as bracesand reinforcing means for the side forms. They will also prevent thesoft concrete from passing through the openings in the grooving stripand filling up the inside of the grooving strip and will secure thegrooving strip to the web 10.

It will be observed that these bars 41 may be five feet in length andthat approximately thirty inches of this length will have to passthrough the openings of the side form and the grooving strip during thestripping operation. In other words, the side form and grooving stripwill have to strip over approximately thirty inches of the free end ofthe bar in order to entirely release the form from the edge of theroadway. Furthermore, it should be understood that in some cases thereare four of these barstwo to the ten foot section :of the road form.Sometimes it is specified that these bars be spaced as close as twelveinches. Therefore, whatever resistance there is to stripping the formover one bar may be multiplied twenty to fifty times. However, with theuse of the tubular members 19 and the sleeves 46 of this invention theresistance to stripping will be negligible. Where the dowel bars 41 areprovided with lugs 49 as shown in Figures 7, 8 and 9, the sleeves 19 and46 are particularly useful in that the lugs 49 would be apt to catchagainst narrow openings such as the opening 20 in the web 10 and theopening 21 in the wall 16. The tubes 19"and 47 affordsufiici'e'nt'a'xial elongated bearing surfaces so as to receive two ormore, of the lugs 49 which tends to axially stabilize the dowel bars 41.This is especially true in the staggered form of the lugs 49 shown inFigure 7 as the axial distance between staggered lugs 49 on oppositesides of the dowel bars is sufliciently short so that proximate lugs 49are contained simultaneously even in the short sleeve 19. Of course agreat number of the lugs 49 are simultaneously housed within the longersleeve 46 as shown in Figure 4.

It has been discovered in dismantling old concrete structures that whendowel bars are placed in position and the concrete poured, as describedabove in the use of the improved side form, there is honey-combing orvoiding of the dowel, as indicated in Figure 11 of the drawings. In thisFigure 11, 41 represents the dowel when placed in position andthereafter concrete 48a has been poured over the dowel resulting in thehoney-combing of the concrete immediately under the dowel, as indicatedat 41c. It will be noted that this voiding destroys the value of thedowel bearing and depreciates the stability of the structure and weakensthe load transfer efficiency of the dowel. The dowel bars may bevibrated into the plastic material to avoid this honey-combing of thecon crete around the bars.

Figures 5 and illustrate the method of installing the dowel bars afterthe concrete has been poured and before the concrete sets or hardens.The usual method of installing dowel bars has been to stake the dowel ortie bar in position some times by method of wiring or otherwise, anexpensive or slip-shod method of positioning the bar which is insecureand expensive. With the tubular supporting members 19 and 46, asillustrated, it is important to pour the concrete as indicated at 48 andwhile the concrete is yet plastic to force the dowel bar through thetubular supporting member. Sometimes these dowel bars are as much as twoinches in diameter so in order to preclude the possibility of theconcrete flowing into the large opening in the large tube 46, whichwould be approximately 2% in diameter, the practice would be to positionthe dowel bar into the tube with the end of the dowel bar flush with theinside of the form where it contacts the concrete as indicated at 41b.This would block the concrete from entering into the tube and after theconcrete has been poured, and while it is yet plastic, force the dowelbar through the tube support and into the plastic concrete for thedesired distance. The same procedure may be followed in installing thebars through the tubular members 19 and the openings 51.

It is obvious that various changes and modifications may be made in thedetails of construction and design of the above specifically describedembodiment of this invention without departing from the spirit thereof,such changes and modifications being restricted only by the scope of thefollowing claims:

What I claim is:

1. A dowel bar supporting form comprising a side form having a verticalweb, a grooving strip, a tubular member securing said strip to said web,said tubular member having a smooth through bore for receivingtherethrough a dowel bar, and a support carried by said form and havinga through passageway in alignment with the bore of said tubular memberfor receiving therethrough the dowel bar.

2. A dowel bar supporting form comprising a side form having a verticalweb, a grooving strip, a tubular member securing said strip to said web,said tubular member having a smooth through bore for receivingtherethrough a dowel bar, a support carried by said form and having athrough passageway in alignment with the bore of said tubular member forreceiving therethrough the dowel bar, said support and said form havingaligned apertures therethrough for receiving a stake adapted to bedriven into the subgrade for anchoring said form.

3. A dowel bar supporting side form for an airport runway or, the likecomprising a base for resting upon the subgrade, a substantiallyvertical web on said base, a grooving strip, said web and grooving striphaving a series of pairs of horizontally aligned openings, a tubularmember extending through each pair of aligned openings and having theiropposite ends extending beyond said web and said grooving strip, theextended end portions being rolled over to provide lips for engagingsaid web and grooving strip for securing the grooving strip to said web,and a series of horizontally spaced apart supports disposed in alignmentwith said tubular members and secured to said base and web, each supporthaving a through passageway in alignment with the bore of one of saidtubular members, whereby a dowel bar may be received and supported byeach tubular member and its associated passageway.

4. A dowel bar supporting side form for an airport runway or the likecomprising a base for resting upon the subgrade, a substantiallyvertical web on said base, a grooving strip, said web and grooving striphaving a series of pairs of horizontally aligned openings, a tubularmember extending through each pair of aligned openings and having theiropposite ends extending beyond said web and said grooving strip, theextended end portions being rolled over to provide lips for engagingsaid web and grooving strip for securing the grooving strip to said web,a series of horizontally spaced apart supports disposed in alignmentwith said tubular members and secured to said base and web, each supporthaving a through passageway in alignment with the bore of one of saidtubular members whereby a dowel bar may be re ceived and supported byeach tubular member and its associated passageway, each support havingan aperture therethrough, said base having a series of apertures one ofwhich is in alignment with the aperture in each of the supports, each ofsaid pairs of aligned apertures adapted to receive therethrough a stakefor anchoring the form to the subgrade.

5. A dowel bar supporting side form for an airport runway or the likecomprising a base for resting upon the subgrade, a substantially vericalweb on said base, a grooving strip, said web and grooving strip having aseries of pairs of horizontally aligned openings, a tubular memberextending through each pair of aligned openings and having theiropposite ends extending beyond said web and said grooving strip, theextended end portions being rolled over to provide lips for engagingsaid web and grooving strip for securing the grooving strip to said web,a series of horizontally spaced apart supports disposed in alignmentwith said tubular members and secured to said base and web, each supporthaving a through passageway in alignment with the bore of one of saidtubular members, whereby a dowel bar may be received and supported byeach tubular member and its associated passageway, and a brace securedto said supports and having an opening in registry with the passagewayin each support for the reception of the dowel bar.

6. A dowel bar supporting side form for an airport runway or the likecomprising a base for resting upon the subgrade, a substantiallyvertical web on said base, a grooving strip, said web and grooving striphaving a series of pairs of horizontally aligned openings, a series ofhorizontally spaced apart supports secured to said base and web and eachhaving a through passageway in alignment with each pair of openings insaid web and strip, and a sleeve extending through each pair of alignedopenings and passageway and secured to said web and said strip forreceiving and supporting a dowel bar.

7. A support for dowel bars comprising a side form having openings,tubes lining the openings and having smooth bores to receive the dowelbars, supports in the form having dowel bar openings alined with saidtube, and a brace spanning the supports and also having dowel baropenings alined with the tubes and first-named openings.

8. A dowel bar support comprising a side form, a form support therein, abrace for the form support, and a tube lying through said form, supportand brace for slidably receiving a dowel bar therethrough.

9. A dowel bar support comprising a side form, a grooving memberthereon, a form support in the form, a brace for the form support, and atube lying through said form, grooving member, support and brace forslidably receiving a dowel bar therethrough.

10. A dowel bar support comprising a side form, spaced supports in theform, a brace connecting said supports, said form, supports and bracehaving aligned openings for dowel bars, and said form and brace betweenthe supports having other aligned openings to receive dowel bars, andtubes lining the openings and having smooth bores therethrough.

References Cited in the file of this patent UNITED STATES PATENTSHeltzel -1 12111.. Kimmel et a1. Aug. Germain Oct. Miller lune HeltzelJan.

Muntz Feb,

Sarosdy Aug. Allen Mar.

Bean Nov.

